ITS manages Device Tables and Interrupt Translation Tables on its own, so generally we are not interested in maintaining any coherence with CPU's view of those memory regions, except one case: ITS requires that Interrupt Translation Tables should be initialized with zeroes. Existing code already does this, but it does not cleans caches afterwards. This means that ITS may see un-initialized ITT and CPU can overwrite portions of ITT later, when it finally decides to flush caches. Visible effect of this issue that there are not interrupts delivered from a device.
Fix this by calling clean_and_invalidate_dcache_va_range() for newly allocated ITT. Signed-off-by: Volodymyr Babchuk <[email protected]> --- Changes since v1: - Use clean_and_invalidate_dcache_va_range() instead of clean_dcache_va_range() - Do this unconditionally - Do not rename HOST_ITS_FLUSH_CMD_QUEUE into HOST_ITS_FLUSH_BUFFERS --- xen/arch/arm/gic-v3-its.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/xen/arch/arm/gic-v3-its.c b/xen/arch/arm/gic-v3-its.c index 3aa4edda10..8afcd9783b 100644 --- a/xen/arch/arm/gic-v3-its.c +++ b/xen/arch/arm/gic-v3-its.c @@ -685,6 +685,9 @@ int gicv3_its_map_guest_device(struct domain *d, if ( !itt_addr ) goto out_unlock; + clean_and_invalidate_dcache_va_range(itt_addr, + nr_events * hw_its->itte_size); + dev = xzalloc(struct its_device); if ( !dev ) goto out_unlock; -- 2.42.0
